There are several conditions of the inner ear including noise-induced hearing loss, age-induced hearing loss (e.g. presbycusis), tinnitus and others. Presbycusis is the loss of hearing that gradually occurs in most individuals as they grow older. About 30-35 percent of adults between the ages of 65 and 75 years have a hearing loss. It is estimated that 40-50 percent of people 75 and older have a hearing loss.
The loss associated with presbycusis is usually greater for high-pitched sounds. For example, it may be difficult for someone to hear the nearby chirping of a bird or the ringing of a telephone. However, the same person may be able to hear clearly the low-pitched sound of a truck rumbling down the street.
There are many causes of presbycusis. Most commonly it arises from changes in the inner ear of a person as he or she ages, but presbycusis can also result from changes in the middle ear or from complex changes along the nerve pathways leading to the brain. Presbycusis most often occurs in both ears, affecting them equally. Because the process of loss is gradual, people who have presbycusis may not realize that their hearing is diminishing.
With presbycusis, sounds often seem less clear and lower in volume. This contributes to difficulty hearing and understanding speech. Individuals with presbycusis may experience several of the following: The speech of others seems mumbled or slurred. High-pitched sounds such as “s” and “th” are difficult to hear and tell apart. Conversations are difficult to understand, especially when there is background noise. A man's voice is easier to hear than the higher pitches of a woman's voice. Certain sounds seem annoying or overly loud. Tinnitus (a ringing, roaring, or hissing sound in one or both ears) may also occur.
Currently, treatment options for presbycusis include treatment of postulated underlying causes, such as hypertension; hearing aids or a cochlear implant; assistive listening devices, such as telephone amplifiers; and removal of earwax. There are no clinically proven remedies for hearing loss.